Abstract
The effects of the several factors, namely, the friction coefficient between the golf ball and club head, the eccentric hitting, the inclination of the head and the shape of surface, on the release velocity, the spin velocity and the distance and direction of the flying ball after impact, are investigated. A computer program that analyzes the dynamic contact problem with friction is developed and the impact phenomenon between the head and ball is numerically analyzed using this program. The effects of the factors described above are investigated quantitatively. it is shown that back spin is the result of friction between the head and ball, and side spin is the result of eccentric hitting or inclination of the head, which is called the gear action. In addition, it is shown that the shape of surface influences the trajectory of the ball after impact, which is called the round effect.
